摘要:
                                Provided herein are compounds of formula (I): or a stereoisomer or tautomer thereof, or a pharmaceutically acceptable salt of any of the foregoing, whereinn, r, p, R1a, R1b, R2, R3, R4, and R5are as defined elsewhere herein. Also provided herein are methods of preparing compounds of formula (I). Also provided herein are methods of inhibiting SLC6A19 and methods of treating a SLC6A19-mediated disease, disorder, or condition in an individual in need thereof.